Hot-melt adhesives are used as laminating adhesives. In the construction industry, waterproof membranes for sealing bases against breakthrough of water have also been used. By way of example, U.S. Pat. No. 4,065,924 describes a barrier layer connected with a top layer, wherein the barrier layer is arranged on the base and the top layer ensures the bond with the poured concrete by being permeated by the poured concrete.
Such waterproof membranes can comprise hot-melt adhesives, which serve as laminating adhesives in order to ensure the bond between the barrier layer and the top layer or directly with the applied concrete. Such hot-melt adhesives can have a variety of properties. In the cured state, the bond strength of the hot-melt adhesive to the barrier layer and the top layer can be high to ensure an optimum protection of the concrete against humidity and water from the base even if the waterproof membrane is damaged. A good adhesion to low-energy materials can be advantageous since in most cases, the barrier layer is prepared from such materials. The adhesion build-up on polyolefin-based materials, for example, polyethylene, can be difficult. In order to ensure the resistance to penetrating water as well, the hot-melt adhesive can penetrate deeply into the top layer before curing. Ideally, after application on the top layer, the concrete penetrates the hot-melt adhesive and binds to the hot melt adhesive, thus resulting in a high resistance to penetrating water. In order to achieve a good binding to concrete, the hot-melt adhesive can have a high inherent tackiness and be as soft as possible after curing. In the case of penetrating water, a high resistance to hydrolysis can be advantageous. In addition, the hot-melt adhesive can have a certain initial tackiness prior to curing in order to enable the barrier layer to bond to the top layer in the industrial manufacture of waterproof membranes.